Case series, chemotherapy-induced cardiomyopathy: mind the family history!

Variants in structural cardiac genes in patients with cancer therapy-related cardiac dysfunction after anthracycline chemotherapy: a case control study

BACKGROUND

Variants in cardiomyopathy genes have been identified in patients with cancer therapy-related cardiac dysfunction (CTRCD), suggesting a genetic predisposition for the development of CTRCD. The diagnostic yield of genetic testing in a CTRCD population compared to a cardiomyopathy patient cohort is not yet known and information on which genes should be assessed in this population is lacking.

METHODS

We retrospectively included 46 cancer patients with a history of anthracycline induced CTRCD (defined as a decrease in left ventricular ejection fraction (LVEF) to < 50% and a ≥ 10% reduction from baseline by echocardiography). Genetic testing was performed for 59 established cardiomyopathy genes. Only variants of uncertain significance and (likely) pathogenic variants were included. Diagnostic yield of genetic testing was compared with a matched cohort of patients with dilated cardiomyopathy (DCM, n = 46) and a matched cohort of patients without cardiac disease (n = 111).

RESULTS

Average LVEF at time of CTRCD diagnosis was 30.1 ± 11.0%. Patients were 52.9 ± 14.6 years old at time of diagnosis and 30 (65.2%) were female. Most patients were treated for breast cancer or lymphoma, with a median doxorubicin equivalent dose of 300 mg/m2 [112.5-540.0]. A genetic variant, either pathogenic, likely pathogenic or of uncertain significance, was identified in 29/46 (63.0%) of patients with CTRCD, which is similar to the DCM cohort (34/46, 73.9%, p = 0.262), but significantly higher than in the negative control cohort (47/111, 39.6%, p = 0.018). Variants in TTN were the most prevalent in the CTRCD cohort (43% of all variants). All (likely) pathogenic variants identified in the CTRCD cohort were truncating variants in TTN. There were no significant differences in severity of CTRCD and in recovery rate in variant-harbouring individuals versus non-variant harbouring individuals.

CONCLUSIONS

In this case-control study, cancer patients with anthracycline-induced CTRCD have an increased burden of genetic variants in cardiomyopathy genes, similar to a DCM cohort. If validated in larger prospective studies, integration of genetic data in risk prediction models for CTRCD may guide cancer treatment. Moreover, genetic results have important clinical impact, both for the patient in the setting of precision medicine, as for the family members that will receive genetic counselling.

Genetic predisposition in chemotherapy-induced cardiomyopathy in a 65-year-old female with metastatic breast cancer

The prevention and management of cancer therapy-related cardiac dysfunction (CTRCD) have become increasingly important. Recent studies have revealed the crucial role of genetics in determining the susceptibility to development of CTRCD. We present a case of a 65-year-old woman with breast cancer who developed recurrent CTRCD following low-dose chemotherapy, despite lacking conventional cardiovascular risk factors. Her medical history included anthracycline-associated cardiomyopathy, and her condition deteriorated significantly after treatment with HER2-targeted therapies. Through the use of multimodal imaging, we detected severe left ventricular systolic dysfunction. Further investigation with genetic testing revealed a likely pathogenic variant in the TNNT2 gene, suggesting a genetic predisposition to CTRCD. This case implies the potential role of genetic screening in identifying patients at risk for CTRCD and advocates for personalized chemotherapy and cardioprotective strategies.

Concealed Inherited Cardiomyopathies Detected in Cardio-Oncology Screening

INTRODUCTION

Basal cardiovascular risk assessment in cardio-oncology is essential. Integrating clinical information, ECG and transthoracic echocardiogram can identify concealed inherited cardiomyopathies (ICMPs) with potential added risk of cardiotoxicity. We aimed to evaluate the impact of our Cardio-Oncology Unit design in detecting concealed ICMPs.

METHODS

We carried out a retrospective study of all consecutive breast cancer patients referred to the Cardio-Oncology Unit for cardiac evaluation (2020-2022). ICMPs diagnosis was provided according to ESC guidelines and underwent genetic testing. ICMPs prevalence in this cohort was compared to the highest and lowest frequency reported in the general population.

RESULTS

Among 591 breast cancer patients, we identified eight patients with ICMPs: one arrhythmogenic cardiomyopathy (ACM), three familial non-ischemic dilated cardiomyopathy (DCM), three hypertrophic cardiomyopathy (HCM) and one left ventricular non-compaction cardiomyopathy (LVNC), which has now been reclassified as non-dilated left ventricular cardiomyopathy. The number of ICMPs identified was within the expected range (neither overdiagnosed nor overlooked): ACM 0.0017 vs. 0.0002-0.001 (p 0.01-0.593); DCM 0.0051 vs. 0.002-0.0051 (p 0.094-0.676); HCM 0.005 vs. 0.0002-0.002 (p < 0.001-0.099); LVCN 0.0017 vs. 0.00014-0.013 (p 0.011-0.015). Genetic testing identified a pathogenic FLNC variant and two pathogenic TTN variants.

CONCLUSION

Opportunistic screening of ICMPs during basal cardiovascular risk assessment can identify high-risk cancer patients who benefit from personalized medicine and enables extension of prevention strategies to all available relatives at concealed high cardiovascular risk.

Dilated cardiomyopathy and chronic cardiac inflammation: Pathogenesis, diagnosis and therapy

Dilated cardiomyopathy (DCM) is typically defined by left ventricular dilation and systolic dysfunction in the absence of a clear precipitant. Idiopathic disease is common; up to 50% of patients with DCM have no cause found despite imaging, genetic and biopsy assessments. Treatment remains focused on managing symptoms, reducing the risk of sudden cardiac death and ameliorating the structural and electrical complications of disease progression. In the absence of aetiology-specific treatments, the condition remains associated with a poor prognosis; mortality is approximately 40% at 10 years. The role of immune-mediated inflammatory injury in the development and progression of DCM was first proposed over 30 years ago. Despite the subsequent failures of three large clinical trials of immunosuppressive treatment (ATTACH, RENEWAL and the Myocarditis Treatment Trial), evidence for an abnormal adaptive immune response in DCM remains significant. In this review, we summarise and discuss available evidence supporting immune dysfunction in DCM, with a specific focus on cellular immunity. We also highlight current clinical and experimental treatments. We propose that the success of future immunosuppressive treatment trials in DCM will be dependent on the deep immunophenotyping of patients, to identify those with active inflammation and/or an abnormal immune response who are most likely to respond to therapy.

Complete remission of Hodgkin’s lymphoma in a pediatric patient with TTN gene mutation treated with brentuximab vedotin combined chemotherapy without anthracyclines: A case report

Introduction

There is no guideline for the treatment of Hodgkin’s lymphoma (HL) in pediatric patients with titin (TTN) gene mutation and heart failure. We explored the feasibility of using brentuximab vedotin (BV) plus chemotherapy without anthracyclines to treat one pediatric HL patient with TTN mutation.

Case presentation

A 5-year and 7-month male patient was admitted to the hospital due to high fever and shortness of breath. He was diagnosed with stage IV IVB high-risk Hodgkin’s lymphoma (lymphocyte-depleted type) at admission. Echocardiography showed that the left ventricular ejection fraction (LVEF) was 27%. The gene sequencing revealed a pathogenic variant in the TTN gene. Due to the risk of cardiotoxicity of anthracycline, he received 6 cycles of chemotherapy (no anthracyclines), 4 cycles of them plus BV with dosing 1.8 mg/kg, q3w. The tumor was reduced by 77% after 2 cycles of BV and 4 cycles of chemotherapy. At the end of 4 cycles of BV and six courses of chemotherapy, with complete remission achieved, the tumor was reduced by 85%. After 11 months of follow-up, the patient was still in complete remission with no adverse events reported, and his LVEF improved to 62%.

Conclusion

The combination of BV with chemotherapy is effective and well-tolerated for pediatric HL patients with TTN gene mutation.